Re: remap_page_range & mm semaphore

[sgrakkyu@xxxxxxxxxx (Oldani Massimiliano)]

On Mon, Mar 01, 2004 at 08:51:25PM +0100, Frank A. Uepping wrote:
> Hello,
> above the implementation of the function remap_page_range() is this comment:
> 	"Note: this is only safe if the mm semaphore is held when called."
> Is this obsolete, because I can't find such mm semaphore?
>

If you look at mm_struct you find that there's no only page table spinlock but 
also a R/W sem.
This function like others of the same family requires that this sem was already hold.

struct mm_struct {
	.......
	.......
	struct rw_semaphore mmap_sem;
	spinlock_t page_table_lock;
	.......
};

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